Paper number 768

PROCESSING AND CHARACTERIZATION OF SIC FIBER REINFORCED TI-15V-3CR MATRIX COMPOSITES

Y.W. Xun, M.J. Tan

School of Mechanical and Production Engineering, Nanyang Technological University Singapore 639798

Summary

SiC/Ti-15V-3Cr metal matrix composites have been developed using the hot uniaxial pressing of an assembly of Ti-15V-3Cr foils stacked between uniaxial fiber mats. The interfacial microstructures and interfacial reaction kinetics were analyzed with respect to the reactivates of the interface and the relevant elements involved. The recrystallization of matrix materials played a great role in refining the matrix grain size, improving the diffusion bonding of matrix/matrix interface as well as fiber/matrix interface. A layer of chemical reaction products mainly consisting of titanium carbides was observed at the fiber/matrix interfaces. Limited reactions were observed compared with those that occurred in the SiC/Ti-6Al-4V system due to a lower processing temperature. This advantage was attributed to the temperature dependence of reaction driving-force. Three types of reaction mechanisms were suggested based on the controlling kinetics of reaction rate.

Keywords

titanium matrix composites, consolidation, C-coated SiC fiber, Ti-15V-3Cr alloy, superplastic flow, diffusion bonding, interfacial reaction, reaction rate.